Electromechanical composite drive vehicle power generation system and high voltage battery pack control circuit and method

Abstract

This invention belongs to the field of automatic control technology, specifically relating to a control circuit and method for a power generation system and high-voltage battery pack in an electromechanical hybrid transmission vehicle. The control circuit includes: a bidirectional buck-boost power converter, a high-voltage battery pack, a high-voltage power distribution and safety protection device, a power generation system, an electromechanical management controller, and an occupant operation panel. The technical solution of this invention relates to the matching charging and discharging control of the high-voltage battery pack and power generation system in electromechanical hybrid transmission special vehicles, grid-connected control of the high-voltage battery pack in emergency operating conditions, charging control of the high-voltage battery pack at low temperatures, charging and discharging control of the high-voltage battery at high temperatures, and rapid high-voltage power-on control at low temperatures in electromechanical hybrid transmission special vehicles. This solution utilizes a bidirectional buck-boost power converter to achieve decoupling and coupling control between the high-voltage battery pack and the power bus voltage.

Description

Technical Field

[0001] This invention belongs to the field of automatic control technology, specifically relating to a control circuit and method for a vehicle power generation system and high-voltage battery pack based on electromechanical composite transmission. Background Technology

[0002] With the rapid development of electromechanical hybrid transmission special vehicles, high-voltage battery packs have become an important power source, providing electricity to supplement insufficient generator power during rapid acceleration, off-road conditions, pure electric driving, and vehicle starting. When the generator system and the high-voltage battery pack are directly connected in parallel, the high-voltage battery pack can quickly replenish energy and maintain the relative stability of the grid voltage when there are fluctuations or sudden sharp drops in grid voltage. However, long-term parallel connection between the high-voltage battery pack and the generator system may lead to overcharging or overvoltage faults in the high-voltage battery pack. A topology control circuit is needed to connect the generator system and the high-voltage battery pack, using a bidirectional buck-boost power converter to connect the high-voltage battery pack and the generator controller respectively. The bidirectional buck-boost power converter controls the discharge and charging currents of the high-voltage battery pack. When the required charging and discharging power of the high-voltage battery pack exceeds the design specifications of the bidirectional buck-boost power converter, the bidirectional buck-boost power converter can be short-circuited, and the high-voltage battery pack can be directly connected to the power bus without affecting the overall vehicle's mobility. Summary of the Invention

[0003] (a) Technical problems to be solved The technical problems to be solved by the present invention are: (1) how to achieve decoupling control between the power generation system and the high-voltage battery pack under necessary operating conditions; and (2) how to achieve high-voltage rapid power-on.

[0004] (II) Technical Solution To solve the above-mentioned technical problems, the present invention provides a power generation system and high-voltage battery pack control circuit for an electromechanical composite transmission vehicle. The control circuit includes: a bidirectional step-up / step-down power conversion device, a high-voltage battery pack, a high-voltage power distribution and safety protection device, a power generation system, an electromechanical management controller, and an occupant operation panel. The bidirectional buck-boost power converter is used to realize bidirectional buck-boost control, that is, buck-boost and power control on both sides; the voltage adjustment range on both sides of the bidirectional buck-boost power converter is 0V~1000V. The high-voltage battery pack is a bidirectional energy storage power source, used for both outputting and storing electrical energy. The high-voltage power distribution and safety protection device is used to realize high-voltage power distribution management, online insulation detection, high-voltage power outage discharge control, and to realize the switching control of the high-voltage battery unit directly connected to the bus. The power generation system is used to convert mechanical energy into electrical energy to provide a continuous and stable power supply to the power grid. The power generation system includes a generator and a generator controller. The generator is used to convert mechanical energy into electrical energy, and the generator controller is used to rectify and control the AC power output by the generator, and at the same time to control the DC power output by constant voltage or constant current. The electromechanical management controller is used to realize the power distribution management, comprehensive scheduling and matching control of electrical energy in the electromechanical system; The occupant control panel is used to enable human-computer interaction.

[0005] Furthermore, the present invention also provides a control method for a power generation system and a high-voltage battery pack in an electromechanical hybrid transmission vehicle. The control method is implemented based on the aforementioned control system and includes: a charging and discharging control strategy for the high-voltage battery pack and the power generation system, an emergency operating condition grid connection control strategy for the high-voltage battery pack, a low-temperature high-voltage battery pack charging control strategy, a high-temperature high-voltage battery pack charging and discharging control strategy, and a high-voltage rapid power-on control strategy.

[0006] The charging and discharging control strategies for the high-voltage battery pack and the power generation system include: a high-voltage battery pack discharging control strategy and a high-voltage battery pack charging control strategy.

[0007] The discharge control strategy for the high-voltage battery pack is as follows: The electromechanical management controller sends the required power and duration of the high-voltage battery pack to the bidirectional buck-boost power converter via the bus; When the required output power of the high-voltage battery pack is ≤50kW, it should be continuously output until the SOC of the high-voltage battery pack is ≤25%; When the required output power of the high-voltage battery pack is ≤100kW, it should be continuously output for 30s until the SOC of the high-voltage battery pack is ≤25%; When the required high-voltage output power is ≤150kW, it should be continuously output for 10s until the SOC of the high-voltage battery pack is ≤25%; When the required high-voltage output power is ≥150kW, the electromechanical management controller will issue a command to switch the high-voltage battery pack control mode to the high-voltage power distribution and safety protection device. The high-voltage power distribution and safety protection device will then connect the high-voltage battery pack directly to the power bus via the switching control of the contactor.

[0008] The high-voltage battery pack charging control strategy is as follows: During vehicle operation, when the SOC of the high-voltage battery pack is ≤35%, the bidirectional buck-boost power conversion device limits the charging current of the high-voltage battery pack to ≤75A. When the SOC of the high-voltage battery pack is ≤50%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤50A. When the SOC of the high-voltage battery pack is ≤70%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤25A. When the SOC of the high-voltage battery pack is greater than or equal to 90%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤10A.

[0009] The grid connection control strategy for the high-voltage battery pack under emergency conditions is as follows: When the bidirectional step-up / step-down power converter malfunctions or when the high-voltage battery pack needs to be directly connected in parallel with the power bus, the control mode of the high-voltage battery pack can be switched by pressing the high-voltage battery pack control mode button on the vehicle control panel, thus enabling the high-voltage battery pack to be connected to the power bus.

[0010] The charging control strategy for the low-temperature high-voltage battery pack is as follows: In low-temperature starting conditions, when the generator starts successfully (i.e., when the generator speed exceeds 1400 rpm) and the temperature of the high-voltage battery pack is ≤0℃, the bidirectional step-up / step-down power converter will prohibit the charging of the high-voltage battery pack.

[0011] The charging and discharging control strategy for the high-temperature, high-pressure battery pack is as follows: Under vehicle operating conditions, when the temperature of the high-voltage battery pack is ≥60℃, the bidirectional buck-boost power converter limits the discharge current of the high-voltage battery pack to ≤30A and the charging current to ≤20A; when the temperature of the high-voltage battery pack is ≥70℃, the bidirectional buck-boost power converter limits the discharge current of the high-voltage battery pack to ≤10A and the charging current to ≤5A; when the temperature of the high-voltage battery pack is ≥72℃, charging and discharging of the high-voltage battery pack is prohibited.

[0012] The high-voltage rapid power-on control strategy is as follows: When high voltage is applied, the high voltage power distribution and safety protection device first performs self-test and insulation test. After the test is normal, the high voltage power distribution and safety protection device connects to the high voltage contactor of the general electrical equipment branch. The high voltage power distribution and safety protection device sends this information to the bidirectional step-up and step-down power conversion device. After the bidirectional step-up and step-down power conversion device detects that there is input voltage on the high voltage battery pack side, it pre-charges the vehicle's electrical equipment. After the pre-charging is completed, it sends a power-on completion signal to the high voltage power distribution and safety protection device. The high voltage power distribution and safety protection device then feeds back the power-on completion information to the passenger control panel, and the high voltage power-on button indicator light on the passenger control panel is illuminated; thus, the high voltage power-on is complete.

[0013] (III) Beneficial Effects Compared with the prior art, the technical solution of this invention involves the matching charging and discharging control of high-voltage battery pack and power generation system in electromechanical hybrid transmission special vehicles, grid connection control of high-voltage battery pack in emergency working conditions of electromechanical hybrid transmission special vehicles, charging control of high-voltage battery pack in low temperature conditions of electromechanical hybrid transmission special vehicles, charging and discharging control of high-voltage battery in high temperature conditions of electromechanical hybrid transmission special vehicles, and high-voltage rapid power-on control in low temperature conditions of electromechanical hybrid transmission special vehicles. This solution utilizes a bidirectional step-up and step-down power conversion device to achieve decoupling and coupling control between high-voltage battery pack and power bus voltage. Attached Figure Description

[0014] Figure 1 This is a block diagram of the topology control circuit for the power generation system and the high-voltage battery group. Detailed Implementation

[0015] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0016] To solve the above-mentioned technical problems, the present invention provides a power generation system and high-voltage battery pack control circuit for an electromechanical composite transmission vehicle. The control circuit includes: a bidirectional step-up / step-down power conversion device, a high-voltage battery pack, a high-voltage power distribution and safety protection device, a power generation system, an electromechanical management controller, and an occupant operation panel. The bidirectional buck-boost power converter is used to realize bidirectional buck-boost control, that is, buck-boost and power control on both sides; the voltage adjustment range on both sides of the bidirectional buck-boost power converter is 0V~1000V. The high-voltage battery pack is a bidirectional energy storage power source, used for both outputting and storing electrical energy. The high-voltage power distribution and safety protection device is used to realize high-voltage power distribution management, online insulation detection, high-voltage power outage discharge control, and to realize the switching control of the high-voltage battery unit directly connected to the bus. The power generation system is used to convert mechanical energy into electrical energy to provide a continuous and stable power supply to the power grid. The power generation system includes a generator and a generator controller. The generator is used to convert mechanical energy into electrical energy, and the generator controller is used to rectify and control the AC power output by the generator, and at the same time to control the DC power output by constant voltage or constant current. The electromechanical management controller is used to realize the power distribution management, comprehensive scheduling and matching control of electrical energy in the electromechanical system; The occupant control panel is used to enable human-computer interaction.

[0017] Furthermore, the present invention also provides a control method for a power generation system and a high-voltage battery pack in an electromechanical hybrid transmission vehicle. The control method is implemented based on the aforementioned control system and includes: a charging and discharging control strategy for the high-voltage battery pack and the power generation system, an emergency operating condition grid connection control strategy for the high-voltage battery pack, a low-temperature high-voltage battery pack charging control strategy, a high-temperature high-voltage battery pack charging and discharging control strategy, and a high-voltage rapid power-on control strategy.

[0018] The charging and discharging control strategies for the high-voltage battery pack and the power generation system include: a high-voltage battery pack discharging control strategy and a high-voltage battery pack charging control strategy.

[0019] The discharge control strategy for the high-voltage battery pack is as follows: The electromechanical management controller sends the required power and duration of the high-voltage battery pack to the bidirectional buck-boost power converter via the bus; When the required output power of the high-voltage battery pack is ≤50kW, it should be continuously output until the SOC of the high-voltage battery pack is ≤25%; When the required output power of the high-voltage battery pack is ≤100kW, it should be continuously output for 30s until the SOC of the high-voltage battery pack is ≤25%; When the required high-voltage output power is ≤150kW, it should be continuously output for 10s until the SOC of the high-voltage battery pack is ≤25%; When the required high-voltage output power is ≥150kW, the electromechanical management controller will issue a command to switch the high-voltage battery pack control mode to the high-voltage power distribution and safety protection device. The high-voltage power distribution and safety protection device will then connect the high-voltage battery pack directly to the power bus via the switching control of the contactor.

[0020] The high-voltage battery pack charging control strategy is as follows: During vehicle operation, when the SOC of the high-voltage battery pack is ≤35%, the bidirectional buck-boost power conversion device limits the charging current of the high-voltage battery pack to ≤75A. When the SOC of the high-voltage battery pack is ≤50%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤50A. When the SOC of the high-voltage battery pack is ≤70%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤25A. When the SOC of the high-voltage battery pack is greater than or equal to 90%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤10A.

[0021] The grid connection control strategy for the high-voltage battery pack under emergency conditions is as follows: When the bidirectional step-up / step-down power converter malfunctions or when the high-voltage battery pack needs to be directly connected in parallel with the power bus, the control mode of the high-voltage battery pack can be switched by pressing the high-voltage battery pack control mode button on the vehicle control panel, thus enabling the high-voltage battery pack to be connected to the power bus.

[0022] The charging control strategy for the low-temperature high-voltage battery pack is as follows: In low-temperature starting conditions, when the generator starts successfully (i.e., when the generator speed exceeds 1400 rpm) and the temperature of the high-voltage battery pack is ≤0℃, the bidirectional step-up / step-down power converter will prohibit the charging of the high-voltage battery pack.

[0023] The charging and discharging control strategy for the high-temperature, high-pressure battery pack is as follows: Under vehicle operating conditions, when the temperature of the high-voltage battery pack is ≥60℃, the bidirectional buck-boost power converter limits the discharge current of the high-voltage battery pack to ≤30A and the charging current to ≤20A; when the temperature of the high-voltage battery pack is ≥70℃, the bidirectional buck-boost power converter limits the discharge current of the high-voltage battery pack to ≤10A and the charging current to ≤5A; when the temperature of the high-voltage battery pack is ≥72℃, charging and discharging of the high-voltage battery pack is prohibited.

[0024] The high-voltage rapid power-on control strategy is as follows: When high voltage is applied, the high voltage power distribution and safety protection device first performs self-test and insulation test. After the test is normal, the high voltage power distribution and safety protection device connects to the high voltage contactor of the general electrical equipment branch. The high voltage power distribution and safety protection device sends this information to the bidirectional step-up and step-down power conversion device. After the bidirectional step-up and step-down power conversion device detects that there is input voltage on the high voltage battery pack side, it pre-charges the vehicle's electrical equipment. After the pre-charging is completed, it sends a power-on completion signal to the high voltage power distribution and safety protection device. The high voltage power distribution and safety protection device then feeds back the power-on completion information to the passenger control panel, and the high voltage power-on button indicator light on the passenger control panel is illuminated; thus, the high voltage power-on is complete.

[0025] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A control circuit for a power generation system and high-voltage battery pack in an electromechanical hybrid transmission vehicle, characterized in that, The control circuit includes: a bidirectional step-up / step-down power converter, a high-voltage battery pack, a high-voltage power distribution and safety protection device, a power generation system, an electromechanical management controller, and an occupant operation panel; The bidirectional buck-boost power converter is used to realize bidirectional buck-boost control, that is, buck-boost and power control on both sides; the voltage adjustment range on both sides of the bidirectional buck-boost power converter is 0V~1000V. The high-voltage battery pack is a bidirectional energy storage power source, used for both outputting and storing electrical energy. The high-voltage power distribution and safety protection device is used to realize high-voltage power distribution management, online insulation detection, high-voltage power outage discharge control, and to realize the switching control of the high-voltage battery unit directly connected to the bus. The power generation system is used to convert mechanical energy into electrical energy to provide a continuous and stable power supply to the power grid. The power generation system includes a generator and a generator controller. The generator is used to convert mechanical energy into electrical energy, and the generator controller is used to rectify and control the AC power output by the generator, and at the same time to control the DC power output by constant voltage or constant current. The electromechanical management controller is used to realize the power distribution management, comprehensive scheduling and matching control of electrical energy in the electromechanical system; The occupant control panel is used to enable human-computer interaction.

2. A control method for a power generation system and high-voltage battery pack in an electromechanical hybrid transmission vehicle, characterized in that, The control method is implemented based on the control system described in claim 1, and the control method includes: a high-voltage battery pack and power generation system charging and discharging control strategy, an emergency operating condition high-voltage battery pack grid connection control strategy, a low-temperature high-voltage battery pack charging control strategy, a high-temperature high-voltage battery pack charging and discharging control strategy, and a high-voltage rapid power-on control strategy.

3. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 2, characterized in that, The charging and discharging control strategies for the high-voltage battery pack and the power generation system include: a high-voltage battery pack discharging control strategy and a high-voltage battery pack charging control strategy.

4. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 3, characterized in that, The discharge control strategy for the high-voltage battery pack is as follows: The electromechanical management controller sends the required power and duration of the high-voltage battery pack to the bidirectional buck-boost power converter via the bus; When the required output power of the high-voltage battery pack is ≤50kW, it should be continuously output until the SOC of the high-voltage battery pack is ≤25%; When the required output power of the high-voltage battery pack is ≤100kW, it should be continuously output for 30s until the SOC of the high-voltage battery pack is ≤25%; When the required high-voltage output power is ≤150kW, it should be continuously output for 10s until the SOC of the high-voltage battery pack is ≤25%; When the required high-voltage output power is ≥150kW, the electromechanical management controller will issue a command to switch the high-voltage battery pack control mode to the high-voltage power distribution and safety protection device. The high-voltage power distribution and safety protection device will then connect the high-voltage battery pack directly to the power bus via the switching control of the contactor.

5. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 4, characterized in that, The high-voltage battery pack charging control strategy is as follows: During vehicle operation, when the SOC of the high-voltage battery pack is ≤35%, the bidirectional buck-boost power conversion device limits the charging current of the high-voltage battery pack to ≤75A. When the SOC of the high-voltage battery pack is ≤50%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤50A. When the SOC of the high-voltage battery pack is ≤70%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤25A. When the SOC of the high-voltage battery pack is greater than or equal to 90%, the bidirectional buck-boost power converter limits the charging current of the high-voltage battery pack to ≤10A.

6. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 5, characterized in that, The grid connection control strategy for the high-voltage battery pack under emergency operating conditions is as follows: When the bidirectional step-up / step-down power converter malfunctions or when the high-voltage battery pack needs to be directly connected in parallel with the power bus, the control mode of the high-voltage battery pack can be switched by pressing the high-voltage battery pack control mode button on the vehicle control panel, thus enabling the high-voltage battery pack to be connected to the power bus.

7. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 6, characterized in that, The charging control strategy for the low-temperature high-voltage battery pack is as follows: In low-temperature starting conditions, when the generator starts successfully (i.e., when the generator speed exceeds 1400 rpm) and the temperature of the high-voltage battery pack is ≤0℃, the bidirectional step-up / step-down power converter will prohibit the charging of the high-voltage battery pack.

8. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 7, characterized in that, The charging and discharging control strategy for the high-temperature, high-pressure battery pack is as follows: Under vehicle operating conditions, when the temperature of the high-voltage battery pack is ≥60℃, the bidirectional buck-boost power converter limits the discharge current of the high-voltage battery pack to ≤30A and the charging current to ≤20A; when the temperature of the high-voltage battery pack is ≥70℃, the bidirectional buck-boost power converter limits the discharge current of the high-voltage battery pack to ≤10A and the charging current to ≤5A; when the temperature of the high-voltage battery pack is ≥72℃, charging and discharging of the high-voltage battery pack is prohibited.

9. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 8, characterized in that, The high-voltage rapid power-on control strategy is as follows: When high voltage is applied, the high voltage power distribution and safety protection device first performs self-test and insulation test. After the test is normal, the high voltage power distribution and safety protection device connects to the high voltage contactor of the general electrical equipment branch. The high voltage power distribution and safety protection device sends this information to the bidirectional step-up and step-down power conversion device. After the bidirectional step-up and step-down power conversion device detects that there is input voltage on the high voltage battery pack side, it pre-charges the vehicle's electrical equipment. After the pre-charging is completed, it sends a power-on completion signal to the high voltage power distribution and safety protection device. The high voltage power distribution and safety protection device then feeds back the power-on completion information to the passenger control panel, and the high voltage power-on button indicator light on the passenger control panel is illuminated; thus, the high voltage power-on is complete.

10. The electromechanical composite transmission vehicle power generation system and high-voltage battery pack control method as described in claim 9, characterized in that, The method utilizes a bidirectional buck-boost power converter to achieve decoupling and coupling control between the high-voltage battery pack and the power bus voltage.

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